...different magnitudes of action potentials. Compound action potentials are also graded, meaning the greater the stimulus, the greater the action potential. 2. Action potentials are said to be all or none responses. Why does the frog sciatic nerve give a graded response? 2. Action potentials are said to be all or none responses. Why does the frog sciatic nerve give a graded response? The frog sciatic nerve gives a graded response de to the nerve being a bundle of axons and not a single axon, resulting in it not showing the “all or none” rule of an axon. In this experiment, if one axon is generating an action potential, then a small nerve impulse will be seen. If all axons are simultaneously generating action potentials, then a large nerve impulse will be seen. This means that the sciatic nerve impulse is graded due to it being able to be none, small, medium, large, or maximal. 3. What was the smallest voltage required to produce the maximum (largest) CAP? What proportion of the nerve fibers were excited to produce this maximal response? 3. What was the smallest voltage required to produce the maximum (largest) CAP? What proportion of the nerve fibers were excited to produce this maximal response? To produce a maximum response, the whole nerve must be stimulated. If the stimulus voltage is increased slowly, you may observe discrete jumps in...
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...this property since they are a bundle of neurons and have different magnitudes of AP's. Thus compound action potentials are graded. That is, the greater the stimulus, the greater the action potential. 2. Action potentials are said to be all or none responses. Why does the frog sciatic nerve give a graded response? The frog sciatic nerve gives a graded response because the nerve is a bundle of axons (CAP) and not a single axon (thus it does not show the all or none response of an axon-either generating an action potential or not). If one axon is generating an action potential then a small nerve impulse is witnessed, if all axons are simultaneously generating action potentials then a large nerve impulse is witnessed. Thus the nerve impulse is graded (it can be none, small, medium, large, larger, maximal). 3. What was the smallest voltage required to produce the maximum (largest) CAP? What proportion of the nerve fibers were excited to produce this maximal response? A minimum of 140 mV is required to produce the maximum Cap. 100% of the excitable nerve fibers were excited to produce the maximal response. We know this because all of the A-alpha fibres making up the nerve have been excited and are conducting action potentials. Even if you were to increase the voltage past 140 mV, the AP would not continue to increase in amplitude. 4. In this exercise, you examined the effect of...
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...Bizarre extinct frog brought back to life March 16, 2013, 10:55 am By environment reporter Sarah Clarke ABC Imagine a frog that can swallow its eggs, brood its young in its stomach and give birth through its mouth. The gastric brooding frog existed 30 years ago, but the extraordinary amphibian is now extinct. In a world first, a team of Australian scientists has taken the first major step in bringing it back to life. They have successfully reactivated its DNA and produced an embryo. Professor Mike Archer from the University of New South Wales is part of the team, which also includes researchers from the University of Newcastle. He says the amphibian was no ordinary frog. "In the stomach these eggs went on to develop into tadpoles and the tadpoles then went on to develop into little frogs," he told ABC radio's AM program. "And like any pregnant mum, when you have little babies rattling away in your stomach saying, 'let me out', she would then open her mouth and out would pop little frogs. "The first people that saw that were aghast. By the time anybody got excited about it, suddenly it was extinct. "So that's certainly one of the driving reasons why this would be a focal animal for seeing if we can de-extinct this amazing frog." That is exactly what a team of Australian scientists is doing. After locating a few carcases stored in a deep freezer, they have been able to recover tissue from the gastric brooding frog. Using a laboratory technique known as somatic cell nuclear transfer...
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...Frogs vs. Toads Frogs and toads are “small, tailless animal” that belongs to the amphibian class. (Forester 536 & Gibbons 303) Everyone thinks that frogs and toads are different from one another but in fact “there is no clear distinction between” them (Burnie & Wilson 440). Most people find it very difficult to differentiate between a frog and a toad that they often mix them up. Their physical features are very much alike but they are different on the basis of anatomy and habitat. When you see a creature hopping along the side of the creek, can you tell if it’s a frog or a toad? Frogs are very unique because “some frogs have colorful markings” (Forester 536). While as toads are marked in a “drab shades of brown, tan, gray, or black that serves as camouflage” (Campbell 217). Besides their markings, “almost all frogs have the same basic body structure” (Forester 536). Frogs have “long, powerful hind legs, which they use for jumping” (Forester 536). “Frogs can leap long distances, but also use their limbs to swim, burrow, and even to glide from tree to tree” (Wake 337). Unlike frogs, toads “generally have squat bodies and short legs” (Campbell 217). They do not “jump” like frogs so they “make short hops or even walk” (Campbell 217). As opposed to skin, frogs have “thin, moist skin” (Forester 536) and “the skin of most toads is dry, rough, and covered with warts” (Gibbons 303). There is an advantage to a toad’s dry skin. It’s “warty skin allows it to inhabit drier regions than...
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...oggy1962 first attempt 1.1 The four basic human body structures and their units are cells, tissues, organs and systems. Cells – these are the smallest independent unit in the human body and can only be seen with a microscope. There are many different types, shapes and sizes. Each type is specialised and carries out a particular function in the body. The types of cells include epithelial cells (the skin), muscle cells, nerve cells, bone cells and blood cells. Every cell has a nucleus, (except red blood cells), a cell membrane and cytoplasm. The nucleus contains the body’s genetic material; this directs all the metabolic activities of the cell. The cell membrane is semi-permeable and surrounds the cytoplasm. Its function is to protect the interior of the cell by allowing certain substances in and keeping others out. The cytoplasm is a gel like substance in which organelles are suspended. These include ribosomes, lysosomes, endoplasmic reticulum, golgi apparatus, mitrochondria, and centrioles. The organelles each have different functions within the cell. Tissues – a group of cells is known as a tissue. Different types of tissues are found in different organs. Humans have four different types of tissue: Epithelial tissue – this covers the body surface. The major functions are protection, secretion, absorption and filtration. Connective tissue – this is the most abundant tissue in the body. It binds structures together and forms a framework and support for organs. It...
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...its mother. 6. Many birds incubate their eggs by sitting on them to keep them warm until they hatch. 7. Emperor and king penguins, which live in Antarctica, warm their eggs by resting them on top of their feet. 8. Many snakes begin life in eggs too, but snake eggs are tough and leathery rather than hard and brittle. 9. A snake called the Indian rock python lays between 50 and 100 eggs at a time. 10. Since snakes are cold blooded, the mother rock python has to twitch her muscles to create heat. 11. During the two months it takes for the eggs to hatch, the mother python stays in one place and dose not even eat. 12. Frogs lay their eggs in jelly – like clumps along the edge of a pond. 13. Mother frogs do not take care of their eggs. 14. When a baby, or tadpole, hatches, it doesn’t look anything like an adult frog. 15. It has a tail, it has no legs or eyes, and it is completely helpless. 16. The tadpole grows legs, its tail begins to shrink, and it looks more and more like its parents. 17. Some baby animals do not hatch from eggs. 18. Mammals differ from other kinds of animals in other ways as well. 19. They are warm blooded, they usually have hair or fur, and their babies are fed with milk that comes from the mother. 20. Kangaroo babies are less than I inch (2.5 centimeters) long when they are...
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...Compare and Contrast Frogs and Toads Frogs vs. Toads When you see a creature hopping a farseeing the side of the creek, bathroom you tell if its a frog frog or a toad? Many people rear end non tell the difference amidst the two. They ar similar in many ways. When flavor at the two, there are some differences in them. For instance the frog and toad both have bulging eye; however, the frogs eyes are s illuminely bigger than the toads. As you read on you will learn the differences and similarities between the frog and toad. There are 2000 known species of the frog compared to the 300 kinds of toads. A frog is a small, slim, four legged amphibian with smooth skin and foresighted powerful hind legs with webbed feet. The biggest frog is the Giant frog, sometimes called Goliath Frog, in West Africa. This Giant frog laughingstock grow up to a foot in length. The frog is green or brown skinned with dark markings, pointed head, long hind legs, and can get one to four inches in length. Some frogs have suckers on their feet which help them cling to tree diagram trunks as they climb, known as tree frogs. The toad on the other hand has dry, warty skin with non as powerful hind legs. Toads are also lucubrate compared to the slim frog. The toad will puff up with conduct at times. Toads walk slow and have shorter legs than the frog. Toads are light brown skinned with brown markings; dry skin, flabby and can get up to three inches in length. The frog belongs to the family Ranidae...
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...Introduction This essay will consider the structure and function of the 11 systems within the human body. It will detail the interrelationship between the nervous system and the musculoskeletal system and between the circulatory system and the lymphatic system. It will then explain the roles of the circulatory and lymphatic systems in the immune response and the role of hormones in metabolism. Human Body Systems The human body is made up of 11 separate but interconnected systems (Sherwood, 2007). These are the skeletal, muscular, circulatory, respiratory, digestive, excretory, nervous, integumentary, immune, endocrine and reproductive systems. The success and survival of the human body is dependent on the ability of separate body systems to work together. The skeletal system provides structure for the human body, stores minerals, produces blood cells and provides protection for delicate organs (Kelly, 2004). 206 bones are connected with ligaments, muscles and tendons, with cartilage, a softer cushion like material, providing protection in jointed areas. Body movements are controlled by the muscular system, with these muscles being connected to bones via tendons (Adams, 2004). Stimulation of these muscles by the nervous system causes contraction and the resulting movement of bones to which they are attached. A number of involuntary muscles ensure the respiratory and circulatory systems continue with contraction of the heart and lungs (Adams, 2004). The heart is central...
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...Cell Theory Cell Theory is a way to describe the biology of living things. Cell theory says that the cell is the basic unit of life. Cells by themselves are alive, but they can also be part of a larger living thing. The smallest living organisms (like bacteria but not viruses) and the biggest ones (like humans and whales) are all made of cells. Very small organisms like bacteria and amoebas are only made of one cell each, so they are called unicellular organisms ("uni" means "one"). Larger organisms are made of many cells, and they are called multicellular organisms. Definition: The Cell Theory is one of the basic principles of Biology. Credit for the formulation of this theory is given to German scientists Theodor Schwann, Matthias Schleiden, and Rudolph Virchow. The Cell Theory states: * All living organisms are composed of cells. They may be unicellular or multicellular. * The cell is the basic unit of life. * Cells arise from pre-existing cells. The modern version of the Cell Theory includes the ideas that: * Energy flow occurs within cells. * Heredity information (DNA) is passed on from cell to cell. * All cells have the same basic chemical composition. Animal Tissues 1. Epithelial: In Greek, ἐπί (epi) means "on" or "upon", and θηλή (thēlē) means "nipple". Epithelial layers are avascular, so they must receive nourishment via diffusion of substances from the underlying connective tissue, through the basement membrane. Epithelia...
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...tissue largely caused by a virus that enters the CNS when the person experiences a viral disease such as measles or mumps or through the bite of a mosquito or tick. 2. Hydrocephalus—An abnormal increase of cerebrospinal fluid in the brain that causes the ventricles of the brain to dialate, resulting in an increased head circumference in the infant with open fontanel(s); a congenital disorder. 3. Neuralgia—Severe, sharp spasmlike pain tht extends along the course of one or more nerves. 4. Narcolepsy—Uncontrolled, sudden attacks of sleep. 5. Dysphagia—difficult speech. 2. Pathologial Conditions 1. Anencephaly—An absence of the brain and spinal cord at birth, a congenital disorder. 2. Bell’s palsy—A temporary or permanent unilateral weakness or paralysis of the muscles in the face following trauma to the face, and unknown infection, or a tumor pressing on the facial nerve rendering it paralyzed. 3. Carpal tunnel syndrome—A pinching or compression of the median nerve within the carpal tunnel due to inflammation and swelling of the tendons, causing intermittent or continuous pain that is greatest at night. 4. Cerebral concussion—A brief interruption of brain function, usually with a loss of consciousness lasting for a few hours. 5. Cerebral contusion--a small, scattered venous hemorrhage in the brain (or better described as a “bruise” of the brain tissue) occurring when the brain strikes the inner skull. 6. Cerebrovascular accident (CVA)—involves...
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...Tikhomirova 1 Tatiana Tikhomirova Marcio Pre-Degree I 3 March 2014 Life Cycle of a Frog Despite the fact that the frog is a small animal, in terms of symbolism, it is of some interest. In ancient Egypt, because of its fertility, as well as a striking transformation from egg to a tadpole, and then in the quadruped animal, the frog was considered strange creature and was a symbol of emerging and ever-renewing life. Often, the ancient gods of care arising out of the mire, depicted with frog heads. Goddess of child-birth, who was a good helper of the popular religion, looked like a frog. (“Heqet”) This essay will describe frog’s transformation from egg to adult frog by three steps. First of all, frogs lay eggs. When multiple eggs stick together, they are collectively known as frogspawn. After fertilization, the innermost portion liquefies to allow free movement of the developing embryo. Most eggs are black or dark brown, and it has the advantage of absorbing heat from the sun, which holds the insulating capsule. Frogs lay a lot of eggs because there are many dangers between fertilization and grown frog. Those eggs that die turn white. Life starts right as the central yolk splits in two. It then divides into four, then eight, etc. Soon, the embryo starts to look more and more like a tadpole, getting longer and moving in egg. Usually, about 6-21 days after being fertilized, the egg will hatch. Most eggs are found in calm or static waters. When the rain comes along, after development...
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...Anurans in Sitio Pahiron Brgy. Lumbia, Cagayan de Oro City A Research Proposal Presented to the Biology Department, Xavier University Cagayan de Oro City In Partial Fulfillment of the Requirements for the Course Seminar and Problem I (Bio 20L) By: Antonette S. Paquera July 2015 APPROVED: Dr. Astrid Sinco Adviser ACCEPTED: Ms. Christine Lovelle Mahinay Reader Project Title: Anurans in Sitio Pahiron Brgy. Lumbia, Cagayan de Oro City Proponent: Antonette S. Paquera Project Duration: 4 months (June 2015-September 2015) Project Budget: Php 55, 680.90 TABLE OF CONTENTS CHAPTER PAGE Title Page A....................................................................................................................i Title Page B....................................................................................................................ii TABLE OF CONTENTS..............................................................................................iii LIST OF FIGURES.......................................................................................................v LIST OF PLATES.........................................................................................................v LIST OF TABLES........................................................................................................v I. Introduction......................................................................................................
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...Blossom and Grueba Blossom and Grueba Deep in a swamp in a faraway town lied a lily pad community known for its marshy waters and remoteness, called Caymaris. Within its population there was a beautiful bullfrog named Blossom whom every one envied, for her long green legs, slender torso, and stunning emerald eyes, she was the talk of the bog. Other Inhabitants all prayed one day to be as alluring as her. Though Blossom was the fairest Bullfrog in her town, her sister Grueba did not have any of these attributes. She was polar opposite of Blossom, the kindest, hardworking Frog you could ever meet. She was always willing to lend a helping hand to anyone in need and volunteered to deliver food to all the hungry frogs of the town. Her torso was compact, round, and her eyes were off centered and as black as coal, and the legs she used to carry out her kindness were short and stumpy. Blossom never wanted any of the bayou to know that Grueba was her sister, for she thought she’d be ridiculed. Daily Blossom would go about her routine of awaking dressing prim and proper even styling her hair with a neatly done ponytail and a gigantic white bow adhering it together. While Grueba's hair was always a mess, and all the kids teased her and called her names. Every morning on their treacherous walk to school across the wetland and through the forest Blossom would be sure to stride far ahead of Grueba, to ensure that none of her classmates could see that they were sisters...
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...not a particularly dominant or influential nation in the world. Unlike its petulant cousin to the north, South HOMETOWN has not garnered much attention from the world. It does not possess plentiful resources, finances or land mass. On a personal level I was once much like my country—insignificant and unnoticeable. I didn't play sports or embark on any adventures or challenges. I lived a boring life. If I were a flavor, I'd be vanilla. At the age __, things changed. A strong desire birthed within me to do something meaningful with my life. Dreams of attending university and plotting a career path dominated my thoughts. Looking around at my situation, I quickly realized that HOMETOWN was not the suitable place to achieve that dream. I was a frog in a well. I began to search for what I felt would be the ideal setting to study and to fulfill my goals. My quest soon culminated with (College). Here was an institution that had all the elements I was looking for as an international student preparing to make a global impact. New York is one of, if not the most, cosmopolitan cities in the world. It thrives with people of various nationalities and ethnicities. Even though the grand stage of __________ is a far cry from my home city, (COLLEGE)'s multicultural student body and international focus is exactly the environment where I'd feel at home. In addition, because of its focus, and international campuses, (COLLEGE)'s academic programs offer relevant, and first-hand perspectives on world...
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...Where did all the frogs go? Imagine years into the future from now, the newly born kids won’t even know what a frog even is, how sad would that be? No more familiar ribbit in the middle of the night. Amphibians are still very important to humans, to the ecosystem, and to predators. If the amphibians become extinct, they will be nothing but a memory. Frogs control pests like flies, mosquitoes, and other insects that have the capability of carrying a disease. If a mosquito is carrying a disease and bites a human, they could get malaria, which can cause death. Frogs decrease the chance for humans to get deadly diseases like that. As amphibians decrease, problems may increase. Loosing fifty percent of the amphibians would put them almost extinct; they are already on the endangered list, which wouldn’t be good if we lost even more of the population. Conversationalists think that because amphibians are small, they are not as important to focus on, but they are wrong. Like mentioned above, amphibians control the insect population. The loss of the amphibians will also cause their predators to die as well. Amphibians have been teaching us many things; they have been alive for 350 million years, surviving dinosaurs, meteors, and also humans. That is a long period of evolutionary success. They adapt to wide range of environments like deserts, forests, and ponds. They still teach us things today, like new medicines and cures that are used from the chemicals within...
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